Search

Carbon dioxide-based polyoxazolidinones (POxa) are an emerging subclass of non-isocyanate polyurethanes for high temperature applications. Current POxa with rigid linkers suffer from limited solubility that hinders synthesis and characterization. Herein, we report the addition of alkyl and alkoxy solubilizing groups to rigid spirocyclic POxa and their poly(hydroxyoxazolidinone) (PHO) precursors. The modified polymers were soluble in up to 6 organic solvents, enabling characterization of key properties (i.e., molar mass and polymer structure) using solution-state methods. Dehydration of PHO to POxa changed solubility from highly polar to less polar solvents and improved thermal stability by 76–102 °C. The POxa had relatively high glass transition (85–119 °C) and melting (190–238 °C) temperatures tuned by solubilizing group structure. The improved understanding of factors affecting solubility, structure-property relationships, and degradation pathways gained in this study broadens the scope of soluble POxa and enables more rational design of this promising class of materials.

Background Moisturizers possibly improve atopic dermatitis (AD) by restoration of skin barrier, although some have detrimental effects. Objective The aim of the study was to estimate the effects of several routine moisturizers on barrier functions. Methods This is a randomized, forearm-controlled, observer-blind study. Patients older than 12 years with clear to moderate AD were randomized to 1 of 4 moisturizers (Cetaphil Cream, Aveeno Eczema Therapy Moisturizing Cream, CeraVe Moisturizing Cream, Vaseline) applied to nonlesional skin of 1 forearm and no moisturizer to the opposite forearm for 4 weeks. Transepidermal water loss (TEWL), capacitance, pH, and TEWL after tape stripping were evaluated at weeks 0 and 4. In addition, participants without AD underwent baseline measurements only. Results Twenty patients with AD completed the study. Baseline measurements between the AD group and 10 non-AD controls were similar. After the intervention (AD group), mean TEWL improved in the treated forearm and worsened in the untreated one, but the difference was not significant. There was no significant change in pH or in TEWL after tape stripping. Capacitance significantly improved in the moisturizer forearm. The study was underpowered as recruitment fell short. Conclusions The effects of moisturizers on nonlesional AD skin were small and need to be addressed when powering future studies. Broadening investigations beyond the classic barrier properties might be useful in future studies.

The effect of the maritime environment on radio frequency (RF) propagation is not well understood. In this work, we study the propagation of ad hoc 2.4 GHz and 5 GHz wireless local area network systems typically used for near-shore operation of unmanned surface vehicles. In previous work, maritime RF propagation performance is evaluated by collecting RSSI data over water and comparing it against existing propagation models. However, the multivariate effect of the maritime environment on RF propagation means that these single-domain studies cannot distinguish between factors unique to the maritime environment and factors that exist in typical terrestrial RF systems. In this work, we isolate the effect of the maritime environment by collecting RSSI data over land and over seawater at two different frequencies and two different ground station antenna heights with the same physical system in essentially the same location. Results show that our 2.4 GHz, 2 m antenna height system received a 2 to 3 dBm path loss when transitioning from over-land to over-seawater (equivalent to a 25 to 40% reduction in range), but increasing the frequency and antenna height to 5 GHz, 5 m respectively resulted in no meaningful path loss under the same conditions, this reduction in path loss by varying frequency and antenna height has not been demonstrated in previous work. In addition, we studied the change in ground reflectivity coefficient, R , when transitioning from over-land to over-seawater. Results show that R remained relatively constant, &minus, 0.49 &le, R &le, &minus, 0.45, for all of the over-land experiments, however, R demonstrated a frequency dependence during the over-seawater experiments, ranging from &minus, 0.39 &le, 0.33 at 2.4 GHz, and &minus, 0.51 &le, 0.50 at 5 GHz.

While the Second Wave of feminism opened doors for female political activism and for women to be seen as strong political leaders, the movement has been accused of focusing largely on the concerns of white women and generally avoiding the concerns of African American women—who live in a double bind of racial and gender discrimination. In this chapter, Nadia E. Brown, Guillermo Caballero, Fernando Tormos, Allison Wong, and Sharonda Woodford argue that despite criticism of Second-Wave feminists for ignoring the intersection of race and gender, the movement, when viewed in conjunction with the African American Civil Rights Movement proved influential for Black women who came of age during this period, launching a generation of female, African American state political leaders. Specifically, Brown and colleagues examine differences in class and generational cohorts among African American female state legislators from 1990 to 2014. They focus primarily on African American female state legislators in the South since that is where most African Americans live and where female African Americans have had the most electoral success. In order to explicate the ways in which race and gender function in tandem, Brown et al. profile two African American female state legislators from Maryland. From this in-depth case study, the authors are able to provide a more nuanced description of how these two legislators championed policies designed to help the most marginalized people in their community—an approach that allows African American legislators to establish common ground at the crucial intersection of race and gender, highlighting the complexity of Black feminism in the post-Second-Wave era.

The purpose of this study was to examine the underlying structure of the second edition of the Test of Gross Motor Development-2 (Ulrich, 2000) as applied to Chinese children. The Test of Gross Motor Development-2 was administered to 626 Hong Kong Chinese children. The outlier test with standard scoring was utilized. After data screening, a total of 614 cases (N = 614) were used for further analysis. The two-factor structure of the Test of Gross Motor Development-2 was tested using confirmatory factor analysis with maximum likelihood estimation to compute parameter estimates and to select the appropriate item for each factor. The goodness-of-fit indices supported that the model was tenable (goodness-of-fit index = .95, root mean square error of approximation = .06, standardized root mean square residual = .04, comparative-fit index = .97). The findings of this study suggested that the two-factor structure proposed by Ulrich (2000) fit the data of Hong Kong Chinese children.

Recognizing inflammatory bowel disease (IBD) is straightforward when alarm symptoms are present, such as bloody diarrhea and weight loss. When the presentation is subtle or atypical, physicians must determine which patients warrant evaluation for IBD. Appropriate use of noninvasive tests can help identify which patients should undergo further investigation.Currently IBD serologies lack high enough sensitivity and specificity to make them useful as a screening test for distinguishing IBD from other disorders, but they may have a role in classifying subtypes of IBD. Fecal markers seem promising for helping to differentiate IBD from irritable bowl syndrome and for monitoring disease activity. Pharmacogenetically guided dosing is recommended for safe use of thiopurines but ongoing routine laboratory monitoring remains important. Thiopurine metabolite measurement can be useful but may not be needed in all cases.Primary care physicians should continue to rely on routine laboratory tests and clinical suspicion to decide which patients with abdominal pain to refer to a gastroenterologist. Serology panels are not useful for IBD screening as the results may lead to unnecessary procedures. Although fecal markers do show promise as a screening test for IBD, patient resistance to providing stool samples may limit its usefulness in disease monitoring. Thiopurine metabolite levels are best used in conjunction with clinical status and routine laboratory tests to monitor clinical response and adverse events.

A young man presented with acute dislocation of the left elbow at the radio-capitellar articulation caused by trapping of the biceps tendon at the stalk of a solitary osteochondroma. There was no deformity of the ulna and radius shaft suggestive of a developmental growth disturbance of the forearm bones. Good reduction could be achieved by simple relocation of the biceps tendon. The osteochondroma was excised.

Pasteurella multocida toxin (PMT) is a potent mitogen known to activate several signaling pathways via deamidation of a conserved glutamine residue in the α subunit of heterotrimeric G-proteins. However, the detailed mechanism behind mitogenic properties of PMT is unknown. Herein, we show that PMT induces protein synthesis, cell migration, and proliferation in serum-starved Swiss 3T3 cells. Concomitantly PMT induces phosphorylation of ribosomal S6 kinase (S6K1) and its substrate, ribosomal S6 protein (rpS6), in quiescent 3T3 cells. The extent of the phosphorylation is time and PMT concentration dependent, and is inhibited by rapamycin and Torin1, the two specific inhibitors of the mammalian target of rapamycin complex 1 (mTORC1). Interestingly, PMT-mediated mTOR signaling activation was observed in MEF WT but not in Gαq/11 knock-out cells. These observations are consistent with the data indicating that PMT-induced mTORC1 activation proceeds via the deamidation of Gαq/11, which leads to the activation of PLCβ to generate diacylglycerol and inositol trisphosphate, two known activators of the PKC pathway. Exogenously added diacylglycerol or phorbol 12-myristate 13-acetate, known activators of PKC, leads to rpS6 phosphorylation in a rapamycin-dependent manner. Furthermore, PMT-induced rpS6 phosphorylation is inhibited by PKC inhibitor, Go6976. Although PMT induces epidermal growth factor receptor activation, it exerts no effect on PMT-induced rpS6 phosphorylation. Together, our findings reveal for the first time that PMT activates mTORC1 through the Gαq/11/PLCβ/PKC pathway. The fact that PMT-induced protein synthesis and cell migration is partially inhibited by rapamycin indicates that these processes are in part mediated by the mTORC1 pathway. Background: Pasteurella multocida toxin (PMT) is a highly mitogenic bacterial protein whose detailed mechanism is not well understood. Results: PMT deamidates and activates Gαq/11 leading to mTORC1 activation. Conclusion: Gαq/11/PLCβ/PKC-mediated mTORC1 activation is at least partially responsible for PMT-induced cell growth, migration, and proliferation in Swiss 3T3 cells. Significance: Understanding PMT-induced mTORC1 activation could help elucidate mechanisms of oncogene regulation.

Pasteurella multocida toxin (PMT) is a mitogenic protein that hijacks cellular signal transduction pathways via deamidation of heterotrimeric G proteins. We previously showed that rPMT activates mTOR signalling via a Gαq/11/PLCβ/PKC mediated pathway, leading in part to cell proliferation and migration. Herein, we show that mTOR and MAPK, but not membrane-associated tyrosine kinases, are activated in serum-starved 3T3 cells by an autocrine/paracrine substance(s) secreted into the conditioned medium following rPMT treatment. Surprisingly, this diffusible factor(s) is capable of activating mTOR and MAPK pathways even in MEF Gαq/11 double knockout cells. Microarray analysis identified connective tissue growth factor (CTGF) mRNA as the most upregulated gene in rPMT-treated serum-starved 3T3 cells relative to untreated cells. These results were further confirmed using RT-PCR and Western blot analysis. In accord with rPMT-induced mTOR activation, upregulation of CTGF protein was observed in WT MEF, but not in Gαq/11 double knockout MEF cells. Although CTGF expression is regulated by TGFβ, rPMT did not activate TGFβ pathway. In addition, MEK inhibitors U0126 or PD98059, but not mTOR specific inhibitors, rapamycin and Torin 1, inhibited rPMT-induced upregulation of CTGF. Importantly, CTGF overexpression in serum-starved 3T3 cells using adenovirus led to phosphorylation of ribosomal protein S6, a downstream target of mTOR. However, despite the ability of CTGF to activate the mTOR pathway, upregulation of CTGF alone could not induce morphological changes as those observed in rPMT-treated cells. Our findings reveal that CTGF plays an important role, but there are additional factors involved in the mitogenic action of PMT.

O-linked glycosylation is a common post-translational modification of apolipoproteins, but no structural or functional role for it has been identified. We examined the biosynthesis of apolipoprotein (apo) A-II in Hep G2 cells and in glycosylation-defective Chinese hamster ovary (CHO) cell mutants transfected with apoA-II cDNA. Three monomeric isoforms of apoA-II with an apparent molecular mass of 8.5, 9.8, and 11.4 kDa were synthesized by Hep G2 cells and transfected wild-type CHO cells. The 9.8- and 11.4-kDa isoforms were sialylated but not the 8.5-kDa isoform. Transfected 1dlD cells, which are defective in the biosynthesis of galactose and N-acetylgalactosamine, only produced the 8.5-kDa isoform; however, when grown in media supplemented with these sugars, ldlD cells produced all three isoforms of apoA-II. Pulse-chase analysis of ldlD cells showed that glycosylation was not necessary for secretion of apoA-II. Glycosylation did modify the association of apoA-II with nascent high density lipoprotein (HDL) secreted by Hep G2 cells. The sialylated isoforms were lipid-poor and were present in the lipoprotein-deficient density range, whereas the nonsialylated 8.5-kDa isoform was associated with LpA-I, A-II lipoprotein particles in the HDL density range. ApoA-II from transfected ldlD cells, regardless of glycosylation, were lipid-poor. When preincubated with HDL from serum, however, sialylated apoA-II from both ldlD cells and Hep G2 cells associated with lipoprotein particles within the HDL3 density, whereas nonsialylated apoA-II was found throughout the HDL density range. In summary, O-linked glycosylation is not necessary for the secretion of apoA-II but does modify the association of apoA-II to HDL and may, therefore, play an important role in the metabolism of HDL.

BACKGROUND AND OBJECTIVE: Aluminum (Al) is associated with significant central nervous system toxicity and bone and liver damage. Because Al is a contaminant of parenteral nutrition (PN) components including calcium and phosphate additives, premature infants are at potentially high risk for toxicity. The US Food and Drug Administration (FDA) has mandated PN component product labeling and recommended maximum Al daily exposure limits. The objective of this article is to determine the actual Al content of neonatal PN solutions, compare these values to the calculated amounts from manufacturers' PN product labels, and ascertain whether the actual Al exposure exceeds the FDA recommended maximum of 5 microg . kg(-1) . day(-1). MATERIALS AND METHODS: Samples from 40 neonatal patient PN solutions were selected for sampling and Al content determination. Samples were also taken from 16 manufacturer's component products used in PN formulation. All of the samples were sent to Mayo Laboratories for Al content measurement. The calculated Al concentrations in PN samples were determined from the manufacturer's labeled content. RESULTS: Both measured and calculated Al concentrations exceeded the FDA recommended safe limit of

We present a rare stage III greater arc fracture-dislocation of the carpus including transscaphoid, transcapitate, and transtriquetral dorsal perilunate fracture-dislocation.

A 36-year-old female saleswoman presented with left upper limb injury in a landslide in 1999. The falling stones and mud caught her left forearm with the elbow in semi-flexion and pronation position. The left wrist was hyperflexed passively by the rushing mud. The patient described a pronated twisting force on her left forearm associated with severe pain. She also had minor head injury but without loss of consciousness. The Glasgow Coma Scale was normal with no retrograde amnesia. On physical examination, her left elbow was held in flexion and hyperpronation with the wrist in flexion. A superficial abrasion was noted on the dorsal surface of the left forearm. The elbow and wrist were swollen. All movements of the elbow and wrist were limited by severe pain. There was no neurological or vascular injury. Radiography of the forearm (Fig. 1) included the left elbow and wrist joint was taken. It revealed antero-lateral dislocation of the radial head at the radio-capitellar joint, dislocation of the proximal and distal radio-ulnar joints without fracture of the left upper limb. The ulnar head was dislocated volar to the carpus and distal radius while the radial head was volar to the proximal ulna. The ulno-humeral articulation was intact. The forearm bones had a criss-cross appearance on the lateral radiograph. An elbow arthrogram showed some leakage of the contrast from the elbow joint and no intra-articular loose cartilage fragments. Closed reduction was performed under general anaesthesia. The distal radio-ulnar joint reduced with pronation of the forearm but the proximal radio-ulnar joint and dislocated radial head could only be reduced with supination of the forearm. Reduction of one end was repeatedly lost during the manipulation of the other end. Eventually, the distal radio-ulnar joint was reduced by pronation of the forearm and held by compression of the distal ulna against the distal radius with one hand. The forearm was then supinated, reducing the proximal radio-ulnar joint and radio-humeral articulation. Both reductions were stable in neutral rotation and no K-wire was required. There was no diastasis seen at the radio-ulnar joints, we presumed the interosseous membrane was intact. A long arm cast was applied for 5 weeks with the forearm in neutral rotation, 90° of elbow flexion, and the wrist in neutral deviation and 25° of dorsiflexion. A course of physiotherapy and occupational therapy was offered. The patient regained full function and range of movement of the elbow and wrist joints 2 months after the cast was removed. Minor degree of instability of the distal radio-ulnar joint was noticed on rocking the ulnar head against the radius on follow-up at 6 months, but this became stable at 1 year. The patient had full recovery of function.